Display device

ABSTRACT

A display device includes a display substrate in which a plurality of sub-pixel areas is defined, a light-emitting diode (“LED”) on the display substrate, a touch sensor electrode on the display substrate and including at least one touch electrode, and a bank separating the plurality of the sub-pixel areas, where each of the plurality of the sub-pixel areas may include a first area in which the LED is disposed and a second area in which the touch sensor electrode is disposed.

This application is a continuation of U.S. patent application Ser. No.15/373,877, filed on Dec. 9, 2016, which claims priority to KoreanPatent Application No. 10-2016-0033302, filed on Mar. 21, 2016, and allthe benefits accruing therefrom under 35 U.S.C. § 119, the content ofwhich in its entirety is herein incorporated by reference.

BACKGROUND 1. Field

One or more exemplary embodiments relate to a display device.

2. Description of the Related Art

A light-emitting diode (“LED”) is one type of a semiconductor element,that is, a p-n junction diode, in which holes and electrons are injectedwhen a forward bias is applied thereto and energy generated byrecombination of the holes and electrons is transformed into light.

The LED may be used in various types of mobile devices such as a smartphone, a lap top computer, a digital camera, a camcorder, a mobileinformation terminal, a tablet personal computer and a watch, and invarious types of electronic devices such as a desk top computer, atelevision (“TV”) set, an outdoor advertisement board, an exhibitiondisplay device, an automobile instrument panel and a head up display(“HUD”).

SUMMARY

One or more exemplary embodiments include a display device whichdisplays images via light-emitting diodes (“LEDs”) and has touchfunctions that can be performed via a touch screen.

Additional exemplary embodiments will be set forth in part in thedescription which follows and, in part, will be apparent from thedescription, or may be learned by practice of the presented exemplaryembodiments.

According to an exemplary embodiment of the invention, a display devicemay include a display substrate having a plurality of sub-pixel areas,an LED above the display substrate, a touch sensor electrode above thedisplay substrate and including at least one touch electrode, and a bankseparating the sub-pixel areas, where each of the plurality of thesub-pixel areas may include a first area in which the LED is disposedand a second area in which the touch sensor electrode is disposed.

According to one or more exemplary embodiments, each of the plurality ofthe sub-pixel areas may be positioned in an opening surrounded by thebank, and the first area in which the LED arranged is disposed and thesecond area in which the touch sensor electrode is disposed may beadjacent to each other in each sub-pixel area.

According to one or more exemplary embodiments, the LED may include afirst contact electrode, a second contact electrode, and a p-n diodearranged between the first and second contact electrodes, where thefirst contact electrode may be arranged on a bottom portion of the LEDand electrically connected to a first electrode connected to a thin filmtransistor, and the second contact electrode may be electricallyconnected to a second electrode arranged on a top portion of the LED.

According to one or more exemplary embodiments, the touch sensorelectrode and the first electrode may be arranged on the same layer.

According to one or more exemplary embodiments, the touch sensorelectrode and the second electrode may be arranged on the same layer.

According to one or more exemplary embodiments, a filling layerembedding the LED may fill the opening and the touch sensor electrodemay be arranged on the filling layer.

According to one or more exemplary embodiments, the touch sensorelectrode may include an electrode operating in a self-capacitancemethod and sense a capacitance change of a single touch electrode, andtouch sensor wirings may be respectively and electrically connected tothe touch sensor electrode and reciprocally exchange electrical signalsof the touch sensor electrodes with an external device.

According to one or more exemplary embodiments, the touch sensorelectrode and the first electrode may be arranged on the same layer, afilling layer may be arranged in the opening, the LED and the touchsensor electrode being embedded in the filling layer, and the touchsensor wiring electrically connected to the touch sensor electrode via acontact hole may be arranged on the filling layer.

According to one or more exemplary embodiments, the filling layer may bearranged in the opening, the LED being embedded in the filling layer,the touch sensor electrode may be arranged on the filling layer, thetouch sensor electrode and the second electrode may be on the samelayer, and the touch sensor wiring may be arranged on the touch sensorelectrode.

According to one or more exemplary embodiments, the touch sensorelectrode may include an electrode operating in a mutual-capacitancemethod and sense a capacitance change occurring between a first touchelectrode and a second touch electrode.

According to one or more exemplary embodiments, the first and secondtouch electrodes and the first or second electrodes may be arranged onthe same layer.

According to one or more exemplary embodiments, a plurality of firsttouch electrodes may be electrically connected via connecting wiringsarranged on a different layer with respect to the first touch electrode,and the second touch electrode may be electrically connected torespective touch sensor wirings.

According to one or more exemplary embodiments, the first and secondtouch electrodes may be separated on different layers.

According to one or more exemplary embodiments, the first touchelectrode and at least one of a gate electrode, a source electrode, anda drain electrode, which are provided in the thin film transistor, maybe arranged on the same layer, and the second touch electrode and thefirst or second electrodes may be arranged on the same layer.

According to one or more exemplary embodiments, the touch sensorelectrode may include an electrode which senses capacitance changesalong an X-axis and a Y-axis crossing the X-axis, and a force sensingelectrode which senses, together with the touch sensor electrode, acapacitance change along a Z-axis perpendicular to the X-axis and theY-axis may be arranged on the display substrate.

According to one or more exemplary embodiments, at least one of functionlayers covering the sub-pixel area may be arranged above the displaysubstrate and the force sensing electrode may be arranged above the atleast one of the function layer.

According to one or more exemplary embodiments, the force sensingelectrode may include a conductive polymer material.

According to one or more exemplary embodiments, a refractive indexmatching layer having a refractive index less than that of the forcesensing electrode may be arranged on at least one surface of the forcesensing electrode.

According to one or more exemplary embodiments, the bank may include afirst bank and a second bank arranged on the first bank, the LED may bearranged in an opening surrounded by the first bank, the second banksurrounding the LED may be arranged on the first bank, and the secondelectrode may be electrically connected to the LED on the second bank.

According to one or more exemplary embodiments, the thin film transistorarranged on a bottom portion of the sub-pixel area may include a gateelectrode, a source electrode, and a drain electrode, the first touchelectrode and at least one of the first electrode, the gate electrode,the source electrode, and the drain electrode may be arranged on thesame layer, and the second touch electrode and the second electrode maybe arranged on the same layer.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other exemplary embodiments will become apparent and morereadily appreciated from the following description of the exemplaryembodiments, taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a perspective view of an exemplary embodiment of a displaydevice;

FIG. 2 is a partially exploded perspective view of an exemplaryembodiment of a touch screen panel;

FIG. 3 is a plan view of the display device, showing an exemplaryembodiment of an arrangement of a light-emitting diode (“LED”) and atouch sensor electrode;

FIG. 4 is a cross-sectional view of a single sub-pixel in FIG. 3;

FIG. 5 is a plan view of another exemplary embodiment of a displaydevice;

FIG. 6 is a plan view of an exemplary embodiment of an arrangement of anLED and a touch sensor electrode;

FIG. 7 is a plan view of another exemplary embodiment of an arrangementof an LED and a touch sensor electrode.

FIG. 8 is a cross-sectional view of another exemplary embodiment of asingle sub-pixel;

FIG. 9 is a cross-sectional view of another exemplary embodiment of asingle sub-pixel;

FIG. 10 is a plan view of another exemplary embodiment of an arrangementof an LED and a touch sensor electrode;

FIG. 11 is a plan view of another exemplary embodiment an arrangement ofan LED and a touch sensor electrode.

FIG. 12 is a cross-sectional view of a single sub-pixel in FIG. 11;

FIG. 13 is a cross-sectional view of another exemplary embodiment of adisplay device;

FIG. 14 is a cross-sectional view of another exemplary embodiment of adisplay device;

FIG. 15 is a cross-sectional view of another exemplary embodiment of adisplay device;

FIG. 16 is a cross-sectional view of another exemplary embodiment of adisplay device;

FIG. 17 is a cross-sectional view of another exemplary embodiment of adisplay device;

FIG. 18 is a cross-sectional view of another exemplary embodiment of adisplay device;

FIG. 19 is a cross-sectional view of another exemplary embodiment of asingle sub-pixel; and

FIG. 20 is a cross-sectional view of another exemplary embodiment of asingle sub-pixel.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments, examplesof which are illustrated in the accompanying drawings, in which likereference numerals refer to like elements throughout. In this regard,the exemplary embodiments may have different forms and should not beconstrued as being limited to the descriptions set forth herein.Accordingly, the exemplary embodiments are merely described below, byreferring to the figures, to explain exemplary embodiments of thedescription. Expressions such as “at least one of,” when preceding alist of elements, modify the entire list of elements and do not modifythe individual elements of the list.

As the invention allows for various changes and numerous exemplaryembodiments, exemplary embodiments will be illustrated in the drawingsand described in detail in the written description. However, this is notintended to limit the invention to particular modes of practice, and itis to be appreciated that all changes, equivalents, and substitutes thatdo not depart from the spirit and technical scope of the invention areencompassed in the invention. In the description of the invention,certain detailed explanations of the related art are omitted when it isdeemed that they may unnecessarily obscure the essence of the invention.

It will be understood that when an element is referred to as being “on”another element, it can be directly on the other element or interveningelements may be therebetween. In contrast, when an element is referredto as being “directly on” another element, there are no interveningelements present.

While such terms as “first,” “second,” etc., may be used to describevarious components, such components must not be limited to the aboveterms. The above terms are used only to distinguish one component fromanother.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms, including “at least one,” unless the content clearly indicatesotherwise. “Or” means “and/or.” As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items. It will be further understood that the terms “comprises”and/or “comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof

Furthermore, relative terms, such as “lower” or “bottom” and “upper” or“top,” may be used herein to describe one element's relationship toanother element as illustrated in the Figures. It will be understoodthat relative terms are intended to encompass different orientations ofthe device in addition to the orientation depicted in the Figures. In anexemplary embodiment, when the device in one of the figures is turnedover, elements described as being on the “lower” side of other elementswould then be oriented on “upper” sides of the other elements. Theexemplary term “lower,” can therefore, encompasses both an orientationof “lower” and “upper,” depending on the particular orientation of thefigure. Similarly, when the device in one of the figures is turned over,elements described as “below” or “beneath” other elements would then beoriented “above” the other elements. The exemplary terms “below” or“beneath” can, therefore, encompass both an orientation of above andbelow.

“About” or “approximately” as used herein is inclusive of the statedvalue and means within an acceptable range of deviation for theparticular value as determined by one of ordinary skill in the art,considering the measurement in question and the error associated withmeasurement of the particular quantity (i.e., the limitations of themeasurement system). For example, “about” can mean within one or morestandard deviations, or within ±30%, 20%, 10%, 5% of the stated value.

The terms used in the specification are merely used to describeexemplary embodiments, and are not intended to limit the invention. Anexpression used in the singular encompasses the expression of theplural, unless it has a clearly different meaning in the context. In thespecification, it is to be understood that the terms such as“including,” “having,” and “comprising” are intended to indicate theexistence of the features, numbers, steps, actions, components, parts,or combinations thereof disclosed in the specification, and are notintended to preclude the possibility that one or more other features,numbers, steps, actions, components, parts, or combinations thereof mayexist or may be added.

The invention will now be described more fully with reference to theaccompanying drawings, in which exemplary embodiments of the inventionare shown. Like reference numerals in the drawings denote like elements,and thus their repetitive description will be omitted.

FIG. 1 is a perspective view of a display device 100 according to anexemplary embodiment.

Referring to FIG. 1, the display device 100 may include a display panel110. The display panel 110 may include an active area AA displayingimages and an inactive area IAA extending outwardly from the active areaAA. According to an exemplary embodiment, the inactive area IAA maysurround the active area AA.

According to an exemplary embodiment, the active area AA may extend in alongitudinal direction of the display panel 110, but the invention isnot limited thereto. According to an exemplary embodiment, the displaypanel 110 may be a rigid or flexible panel.

The display device 100 may include a touch screen panel (“TSP”) whichrecognizes a location where a user contacts the display device 100.

FIG. 2 is a partially exploded perspective view of the TSP 200 accordingto an exemplary embodiment.

Referring to FIG. 2, the TSP 200 may include a plurality of touch sensorelectrodes 230. The plurality of touch sensor electrodes 230 may includea plurality of first touch electrodes 210 and a plurality of secondtouch electrodes 220.

According to an exemplary embodiment, the TSP 200 is an on-cell TSP inwhich the plurality of touch sensor electrodes 230 is arranged in thedisplay panel 110 in FIG. 1. However, a structure of the TSP is notlimited thereto.

According to another exemplary embodiment, the TSP 200 may have anin-cell TSP structure in which the plurality of touch sensor electrodes230 are arranged inside the display panel 110 in FIG. 1 or a hybrid TSPstructure, which is a combination of the on-cell TSP and the in-cell TSPstructures, for example. Thus, the structure of the TSP is not limitedto only one type.

The plurality of first touch electrodes 210 and the plurality of secondtouch electrodes 220 may be alternately arranged relative to each otheron a substrate 201. The substrate 201 may be an encapsulated substratearranged in the display panel 110 in FIG. 1. The plurality of firsttouch electrodes 210 and the plurality of second touch electrodes 220may be arranged in directions crossing each other. Each of the firsttouch electrodes 210 may be a transmission electrode and each of thesecond touch electrodes 220 may be a reception electrode.

According to an exemplary embodiment, the TSP 200 may have amutual-capacitance sensing structure, in which capacitance changes aremeasured at points where the plurality of touch sensor electrodes 230cross each other. However, the structure of the TSP 200 is not limitedthereto. According to another exemplary embodiment, the structure of theTSP 200 may be a self-capacitance sensing structure, in which thecapacitance change is measured at each pixel for touch recognition via asingle touch sensor electrode 230. Thus, the structure of the TSP 200 isnot limited to one type only.

The plurality of first touch electrodes 210 and the plurality of secondtouch electrodes 220 may be arranged on the same layer on the substrate201. In another exemplary embodiment, the plurality of first touchelectrodes 210 and the plurality of second touch electrodes 220 may beseparated from each other on different layers.

A pair of the first touch electrodes 210 arranged adjacent to each otheron the substrate 201 may be electrically connected to each other via afirst touch connector 211. A pair of the second touch electrodes 220arranged adjacent to each other on the substrate 201 may be electricallyconnected to each other via a second touch connector 221. A pair of thesecond touch electrodes 220 may be connected to the second touchconnector 221 arranged on a different layer via a contact hole 241, toavoid interference with the first touch electrode 210.

An insulating layer 250 covering the plurality of first touch electrodes210 and the plurality of second touch electrodes 220 may be arranged onthe substrate 201.

When an input tool such as a user's finger or a pen comes close to orcontacts the substrate 201, the TSP 200 may detect a touch location bymeasuring a capacitance change between the first touch electrode 210 andthe second touch electrode 220.

Research and development on a display device including a TSP with aplurality of micro-LEDs has been conducted.

FIG. 3 is a plan view of an arrangement of a LED 325 and a touch sensorelectrode 326 of a display device 300 according to an exemplaryembodiment. FIG. 4 is a cross-sectional view of a single sub-pixel ofthe display device 300 of FIG. 3.

According to an exemplary embodiment, each of sub-pixels of the displaydevice 300 may include at least one thin film transistor (“TFT”) and atleast one micro-LED. However, the TFT is not necessarily feasible onlyin the structure of FIG. 3, and its number and structure may bevariously changeable.

Referring to FIGS. 3 and 4, the display device 300 may include aplurality of sub-pixel areas 301. The sub-pixel areas 301 may beseparated from each other in the X-axis and the Y-axis directions on adisplay substrate 311. The sub-pixel areas 301 may be separated fromeach other by at least one layer of a bank 323. The sub-pixel area 301may include a first area 302 in which the LED 325 is disposed (e.g.,placed) and a second area 303 in which a touch sensor electrode 326 isplaced.

In an exemplary embodiment, the display substrate 311 may be any one ofa rigid glass substrate, a flexible glass substrate, and a flexiblepolymer substrate, for example. In an exemplary embodiment, the displaysubstrate 311 may be transparent, semi-transparent, or opaque, forexample.

A buffer layer 312 may be arranged on the display substrate 311. Thebuffer layer 312 may totally cover a top surface of the displaysubstrate 311. The buffer layer 312 may include an inorganic layer or anorganic layer. The buffer layer 312 may be a single layer or amulti-layer.

The TFT may be arranged on the buffer layer 311. The TFT may include asemiconductor activating layer 313, a gate electrode 318, a sourceelectrode 320, and a drain electrode 321. According to an exemplaryembodiment, the TFT may be a top gate type. However, the invention isnot limited thereto, and the TFT may be other types such as a bottomgate type.

The semiconductor activating layer 313 may be arranged on the bufferlayer 312.

The semiconductor activating layer 313 may include a source area 314 anda drain area 315 which are positioned by doping n-type impurity ions orp-type impurity ions. An area between the source area 314 and the drainarea 315 may be a channel area 316 in which impurities are not doped. Inan exemplary embodiment, the semiconductor activating layer 313 may bean organic semiconductor, an inorganic semiconductor, or amorphoussilicon, for example. In another exemplary embodiment, the semiconductoractivating layer 313 may be an oxide semiconductor, for example.

A gate insulating layer 317 may be arranged on the semiconductoractivating layer 313. The gate insulating layer 317 may include aninorganic layer. The gate insulating layer 317 may be a single layer ora multi-layer.

The gate electrode 318 may be arranged on the gate insulating layer 317.The gate electrode 318 may include a material with good conductivity.The gate electrode 318 may be a single layer or a multi-layer.

An interlayer insulating layer 319 may be arranged on the gate electrode318. The interlayer insulating layer 319 may include an inorganic layeror an organic layer.

The source electrode 320 and the drain electrode 321 may be arranged onthe interlayer insulating layer 319. In detail, a contact hole may bedefined by removing a portion of the gate insulating layer 317 and aportion of the interlayer insulating layer 319. Then, the sourceelectrode 320 may be electrically connected to the source area 314 viathe contact hole and the drain electrode 321 may be electricallyconnected to the drain area 315 via the contact hole.

A planarization layer 322 may be arranged on the source electrode 320and the drain electrode 321. The planarization layer 322 may include aninorganic layer or an organic layer.

At least one layer of the bank 323 separating the sub-pixel areas 301may be arranged on the planarization layer 322. The bank 323 may includean inorganic layer or an organic layer. The bank 323 may be transparentor opaque. The bank 323 may include a light absorbing material, a lightreflecting material, or a light scattering material. The bank 323 mayfunction as a light blocking layer having low light transmissivity.

An opening 324 may be defined above the TFT by removing a portion of thebank 323. A first electrode 333 may be arranged on the planarizationlayer 322 which is exposed by removing the portion of the bank 323. Thefirst electrode 333 may be electrically connected to the drain electrode321 via the contact hole defined in the planarization layer 322. Thefirst electrode 333 may include a transparent electrode or a metalelectrode. The first electrode 333 may have various patterns. In anexemplary embodiment the first electrode 333 may be patterned in anisland shape, for example.

The sub-pixel area 301 may include the first area 302 in which the LED325 is placed and the second area 303 in which the touch sensorelectrode 326 is placed. The LED 325 and the touch sensor electrode 326may be arranged in the sub-pixel area 301.

In detail, each of the sub-pixel areas 301 may be positioned in theopening 324 surrounded by the bank 323. The first area 302 in which theLED 325 is placed and the second area 303 in which the touch sensorelectrode 326 is placed may be arranged adjacent to each other in eachof the sub-pixel areas 301. According to an exemplary embodiment, a sizeof the second area 303 may be larger than that of the first area 302.

The LED 325 may emit light in a certain wavelength band covering a rangefrom ultraviolet (“UV”) rays to visible light. In an exemplaryembodiment, the LED 325 may be a micro-LED, for example. According to anexemplary embodiment, the LED 325 may be a red-color LED, a green-colorLED, a blue-color LED, a white-color LED, or a UV LED, for example.

The LED 325 may include a first contact electrode 328, a second contactelectrode 329, and a p-n diode 327 arranged between the first contactelectrode 328 and the second contact electrode 329.

The p-n diode 327 may include a p-doped layer 330 on a bottom portion,an n-doped layer 331 on a top portion, and at least one of quantum welllayer 332 arranged between the p-doped layer 330 and the n-doped layer331. In another exemplary embodiment, the doped layer 331 on the topportion may be the p-doped layer and the doped layer 330 on the bottomportion may be the n-doped layer.

The first contact electrode 328 may be arranged on the p-doped layer 330on the bottom portion. The first contact electrode 328 may beelectrically connected to the first electrode 333. The second contactelectrode 329 may be arranged on the n-doped layer 331 on the topportion. The second contact electrode 329 may be electrically connectedto a second electrode 334. The second electrode 334 may include atransparent electrode or a metal electrode. The second electrode 334 mayinclude various shapes of patterns. According to an exemplaryembodiment, the second electrode 334 may be a common electrode.

The touch sensor electrode 326 may be arranged in the second area 303 ofeach of the sub-pixel areas 301. The touch sensor electrode 326 mayinclude a metal layer. In a case of a transparent display device, thetouch sensor electrode 326 may include a transparent conductive layersuch as an indium tin oxide (“ITO”) layer.

The touch sensor electrode 326 may be the same as the touch sensorelectrode 230 in FIG. 2. The touch sensor electrode 326 may extend to anadjacent sub-pixel area 301. According to an exemplary embodiment, thetouch sensor electrode 326 may be a portion of the first touch electrode210 or the second touch electrode 220 in FIG. 2.

The touch sensor electrode 326 may be arranged on a same layer as thaton which the first electrode 333 is disposed. The touch sensor electrode326 may include the same material and be obtained via the same processas that of the first electrode 333. In other exemplary embodiment, thetouch sensor electrode 326 may be patterned with another metallicmaterial.

According to an exemplary embodiment, the touch sensor electrode 326 maybe electrically connected to the first electrode 333. In anotherexemplary embodiment, the touch sensor electrode 326 may apply aseparate electrical signal.

The touch sensor electrode 326 may be driven via a mutual-capacitancemethod or a self-capacitance method, depending on a connection method.

In the case of the mutual-capacitance method, the touch sensor electrode326 may be an electrode which senses a capacitance change between theplurality of touch electrodes such as the first touch electrode 210 andthe second touch electrode 220 in FIG. 2. The plurality of touchelectrodes may be arranged on the same layer above the display substrate311. In another exemplary embodiment, the plurality of touch electrodesmay be separated on different layers above the display substrate 311.

In the case of the self-capacitance method, the touch sensor electrode326 may be an electrode which senses a capacitance change of a singletouch electrode by using a single touch electrode.

According to an exemplary embodiment, a ground wiring (not illustrated)may be further arranged in the second area 303 of the sub-pixel area301.

A filling layer 335 may be filled in the opening 324. The LED 325 andthe touch sensor electrode 326 may be embedded in the filling layer 335.In an exemplary embodiment, the filling layer 335 may include an organicmaterial, but the invention is not limited thereto.

Likewise, the LED 325 may be arranged in the first area 302 of thesub-pixel area 301. The touch sensor electrode 326 may be arranged inthe second area 303 of the sub-pixel area 301.

Below, like reference numbers in illustrated drawings above may denotelike members performing like functions. Thus, duplicate descriptionswill be omitted and only major particular portions of each exemplaryembodiment will be selectively described.

FIG. 5 is a plan view of a display device 500 according to anotherexemplary embodiment.

Referring to FIG. 5, the sub-pixel area 301 may include the first area302 in which the LED 325 is placed and the second area 303 in which atouch sensor electrode 526 is placed. The filling layer 335 may befilled in the opening 324 from which a portion of the bank 323 isremoved.

The LED 325 may be embedded in the filling layer 335. The touch sensorelectrode 526 may be arranged on the filling layer 335. The touch sensorelectrode 526 and the second electrode 334 may be arranged on the samelayer. The touch sensor electrode 526 may include the same material andbe obtained via the same process as that of the second electrode 334.The touch sensor electrode 526 may be driven via a mutual-capacitancemethod or a self-capacitance method, depending on a connection method.

According to an exemplary embodiment, a ground wiring 536 may be furtherarranged in the second area 303 of the sub-pixel area 301. The groundwiring 536 and the touch sensor electrode 526 may be arranged on thesame layer. The ground wiring 536 may eliminate noise caused bypixel-driving. When the ground wiring 536 is arranged, a capacitance maybe reduced, and subsequently, noise may be reduced.

The ground wiring 536 may receive an electrical signal from a powerline, through which a constant voltage flows. In another exemplaryembodiment, a ground voltage may be applied to the ground wiring 536. Inanother exemplary embodiment, the ground wiring 536 may be in a floatingstate.

FIG. 6 is a plan view of an arrangement of the LED 325 and a touchsensor electrode 626 according to an exemplary embodiment.

Referring to FIG. 6, the LED 325 and the touch sensor electrode 626 ofthe display device 600 may be arranged in each of sub-pixel areas 601.Each LED 325 may be arranged in respective sub-pixel areas 601 and thetouch sensor electrode 626 may extend to the adjacent sub-pixel area601. Each of sub-pixel areas 601 may include a first area 602 in whichthe LED 325 is placed and a second area 603 in which a touch sensorelectrode 626 is placed.

An area of the touch sensor electrode 626 may be expanded by enlarging agap g between a pair of LEDs 325 which are involved in differentlight-emitting and adjacent to each other in the X-axis direction. Whenthe area of the touch sensor electrode 626 is increased, touchsensitivity may be enhanced.

According to an exemplary embodiment, the LED 325 arranged in eachsub-pixel may include at least one of the red-color LED, the green-colorLED, the blue-color LED, the white-color LED, and the UV LED. In anotherexemplary embodiment, a color filter layer having color huecorresponding to respective LEDs 325 may be further arranged above theLED 325.

FIG. 7 is a plan view of an arrangement of an LED and a touch sensorelectrode according to another exemplary embodiment.

Referring to FIG. 7, the display device 700 may include a plurality ofsub-pixel areas 701. The sub-pixel areas 701 may be separated from eachother in X-axis and Y-axis directions. The sub-pixel area 701 mayinclude a first area 702 in which the LED 325 is placed and a secondarea 703 in which a touch sensor electrode 726 is placed. The touchsensor electrode 726 may extend to an adjacent sub-pixel area 701.

According to an exemplary embodiment, the touch sensor electrode 726 mayhave a self-capacitance sensing structure. The touch sensor electrode726 may be an electrode which senses a capacitance change in a singletouch electrode. A touch sensor wiring 727 may be arranged on the touchsensor electrode 726. In an exemplary embodiment a plurality of touchsensor wirings 727 may be arranged in the sub-pixel areas 701 which arearranged along the Y-axis direction, for example.

The touch sensor wiring 727 may extend along the Y-axis direction andmay be electrically connected to respective touch sensor electrodes 726which are continuously arranged in the Y-axis direction. The touchsensor wiring 727 may be electrically connected to the touch sensorelectrode 726 and an external device (not illustrated). A changedcapacitance may be transferred from the single touch sensor electrode726 to the external device via the touch sensor wiring 727, and a sensorvoltage generated by the external device may be transferred to the touchsensor electrode 726.

According to an exemplary embodiment, the touch sensor wiring 727 may bedirectly or indirectly connected to the touch sensor electrode 726 onthe touch sensor electrode 726.

Referring to FIG. 8, the sub-pixel area 301 of the display device 800may include the first area 302 in which the LED 325 is placed and thesecond area 303 in which a touch sensor electrode 826 is placed. Thefilling layer 335 may be filled in the opening 324 which is defined byremoving the portion of the bank 323.

The touch sensor electrode 826 and the first electrode 333 may bearranged on the same layer. A touch sensor wiring 827 may be arranged onthe filling layer 335. The touch sensor wiring 827 may be arranged inthe second area 303. The touch sensor wiring 827 may be electricallyconnected to the touch sensor electrode 826 via a contact hole 828defined in the filling layer 335.

According to an exemplary embodiment, the touch sensor wiring 827 and atleast one of the gate electrode 318, the source electrode 320, and thedrain electrode 321 may be included on the same layer. However, thecurrent exemplary embodiment is not limited to a single location.

Referring to FIG. 9, the sub-pixel area 301 of the display device 900may include the first area 302 in which the LED 325 is placed and thesecond area 303 in which a touch sensor electrode 926 is placed. Thefilling layer 335 may be filled in the opening 324 which is defined byremoving the portion of the bank 323.

The touch sensor electrode 926 may be arranged on the filling layer 335.The touch sensor electrode 926 and the second electrode 334 may bearranged on the same layer. A touch sensor wiring 927 may be arranged onthe touch sensor electrode 926. The touch sensor wiring 927 may bedirectly connected to the touch sensor electrode 926.

FIG. 10 is a plan view of an arrangement of the LED 325 and a touchsensor electrode 1026 according to another exemplary embodiment.

Referring to FIG. 10, a display device 1000 may include a plurality ofsub-pixel areas 1001. The sub-pixel areas 1001 may be separated fromeach other in X-axis and the Y-axis directions. The sub-pixel area 1001may include a first area 1002 in which the LED 325 is placed and asecond area 1003 in which the touch sensor electrode 1026 is placed. Thetouch sensor electrode 1026 may extend to an adjacent sub-pixel area1001.

According to an exemplary embodiment, the touch sensor electrode 1026may have a mutual-capacitance sensing structure. The touch sensorelectrode 1026 may be an electrode which senses the capacitance changegenerated between a first touch electrode 1028 and a second touchelectrode 1029. The first touch electrode 1028 and the second touchelectrode 1029 may be arranged on the same layer.

The first touch electrode 1028 and the second touch electrode 1029 maybe alternately arranged in the X-axis direction. The pair of first touchelectrodes 1028, which are separated from each other with the secondtouch electrode 1029 therebetween in the X-axis direction, may beelectrically connected to each other via a connecting wiring 1027 whichis arranged on a different layer with respect to the first touchelectrode 1028. According to an exemplary embodiment, the connectingwiring 1027 may include the same material as that of at least one of thegate electrode, the source electrode, and the drain electrode. Inanother exemplary embodiment, the connecting wiring 1027 may beelectrically connected to any one of the gate electrode, the sourceelectrode, and the drain electrode.

The second touch electrodes 1029 may be respectively connected toseparate touch sensor wirings, or may be directly connected to a touchintegrated circuit (“IC”) on one edge of the display device 1000.

FIG. 11 is a plan view of an arrangement of an LED and a touch sensorelectrode according to another exemplary embodiment, and FIG. 12 is across-sectional view of a single sub-pixel in FIG. 11.

Referring to FIGS. 11 and 12, the display device 1100 may include aplurality of sub-pixel areas 1101. The sub-pixel areas 1101 may beseparated from each other in the X-axis and the Y-axis directions. Thesub-pixel area 1101 may include a first area 1102 in which the LED 325is placed and a second area 1103 in which a touch sensor electrode 1126is placed. The touch sensor electrode 1126 may extend to an adjacentsub-pixel area 1101.

According to an exemplary embodiment, the touch sensor electrode 1126may have the mutual-capacitance sensing structure. The touch sensorelectrode 1126 may include a first touch electrode 1128 and a secondtouch electrode 1129. The first touch electrode 1128 and the secondtouch electrode 1129 may be alternately arranged in the X-axisdirection. Unlike as illustrated in FIG. 10, the first touch electrode1128 and the second touch electrode 1129 may be separated from eachother on different layers.

The first touch electrode 1128, which may be a metal electrode, and asingle electrode arranged on the TFT may be a metal electrode arrangedon the same layer. In an exemplary embodiment, the first touch electrode1128 and the source electrode 320 or the drain electrode 321 may bearranged on the same layer, for example. The first touch electrode 1128may include the same material in the same process as that of the sourceelectrode 320 or the drain electrode 321. In another exemplaryembodiment, the first touch electrode 1128, which may be the metalelectrode, and the gate electrode 318 may be arranged on the same layer.

The second touch electrode 1129 and the first electrode 333 may bearranged on the same layer. The second touch electrode 1129 may includethe same material in the same process as that of the first electrode333. In another exemplary embodiment, the second touch electrode 1129and the second electrode 334 may be arranged on the same layer and mayinclude the same material in the same process.

In another exemplary embodiment, the first touch electrode 1128 mayinclude a separate metal layer, for example, a transparent conductivelayer, and the second touch electrode 1129 and at least one of the gateelectrode 318, the source electrode 320, the drain electrode 321, thefirst electrode 333, and the second electrode 334 may be arranged on thesame layer.

FIG. 13 is a cross-sectional view of a display device 1300 according toanother exemplary embodiment.

Referring to FIG. 13, a first function layer 1301 encapsulating thesub-pixel area 301 may be arranged on the display substrate 311.According to an exemplary embodiment, the first function layer 1301 maybe an encapsulating layer, but it is not limited thereto. A secondfunction layer 1303 may be arranged above the first function layer 1301with a medium layer 1302 therebetween. The second function layer 1303may be a window cover, but it is not limited thereto.

The medium layer 1302 may receive pressure caused by a user's contactand may be a material with a cushion function. According to an exemplaryembodiment, the medium layer 1302 may be an air layer, but it is notlimited thereto. A spacer 1304 maintaining a cell gap may be arrangedbetween the first function layer 1301 and the second function layer1303. A sealant 1305 may be applied to edges where the first functionlayer 1301 and the second function layer 1303 may face.

The sub-pixel area 301 may include the first area 302 in which the LED325 is placed and the second area 303 in which the touch sensorelectrode 326 is placed. The touch sensor electrode 326 and the firstelectrode 333 may be arranged on the same layer. In another exemplaryembodiment, the touch sensor electrode 326 and the second electrode 334may be arranged on the same layer.

The touch sensor electrode 326 may correspond to an electrode whichsenses the capacitance change in the X-axis and the Y-axis crossing theX-axis. A force sensing electrode 1306, which forms capacitance with thetouch sensor electrode 326 in a Z-axis perpendicular to the X-axis andthe Y-axis and senses pressure in accordance with the capacitancechange, may be further arranged on the display substrate 311. Accordingto an exemplary embodiment, the force sensing electrode 1306 may bearranged on one surface of the second function layer 1303 facing thefirst function layer 1301.

Since capacitance is generated between the touch sensor electrode 326and the force sensing electrode 1306, sensing the capacitance change inthe Z-axis may be possible. In detail, when an input tool is pressed, anapplied force may be sensed depending on the capacitance change betweenthe touch sensor electrode 326 and the force sensor electrode 1306.

The force sensor electrode 1306 may patterned with a particular patternon the second function layer 1303. In detail, the force sensor electrode1306 may be patterned with a plurality of patterns having differentareas from each other, to sense each location in accordance with theforce applied to the display device 1300. In another exemplaryembodiment, the force sensor electrode 1306 may be entirely disposed onthe second function layer 1303, to sense the force only.

In an exemplary embodiment, the force sensor electrode 1306 may includeconductive polymer materials such as poly 3,4-ethylenedioxy thiophene(“PEDOT”), polyacetylene, and polypyrrole. Since the force sensorelectrode 1306 has resistance per unit area more than 100 times largerthan that of the transparent conductive layer such as an ITO layer,while maintaining electrical conductivity, the force sensor electrode1306 may be applicable to an electrode of the TSP.

A connector 1307 which is electrically connected to the force sensorelectrode 1306 may be arranged between the first function layer 1301 andthe second function layer 1303. The connector 1307 may be connected to apad on the display substrate 311 via the contact hole 1308 defined inthe first function layer 1301 and may transfer a force sensor signal tothe external device.

Likewise, the structure, in which locations in the X-axis and the Y-axisare sensed by using the touch sensor electrode 326 and a force in theZ-axis is sensed by using the force sensor electrode 1306, may beapplied to various display devices.

Referring to FIG. 14, a display device 1400 may be an organiclight-emitting display device. In detail, a display unit 1402 includingthe TFT and an organic LED may be arranged on a display substrate 1401,a touch sensor electrode 1403 may be arranged on the display unit 1402,and a first function layer 1404 corresponding to encapsulation may bearranged on the touch sensor electrode 1403. A second function layer1406, which corresponds to the window cover, may be arranged above thefirst function layer 1404 with a medium layer 1405 therebetween. A forcesensor electrode 1407 may be arranged on one surface of the secondfunction layer 1406 facing the first function layer 1404.

The touch sensor electrode 1403 may be connected to a pad on the displaysubstrate 1401 via a contact hole 1408 defined in the display unit 1402and may transfer the sensor signal to the external device. In addition,the force sensor electrode 1407 may be connected to a connector 1409 andmay transfer the force sensor signal to the external device.

The structure described above may sense the force applied in accordancewith the capacitance change between the touch sensor electrode 1403 andthe force sensor electrode 1407.

Referring to FIG. 15, a display device 1500 may be an organiclight-emitting display device. In detail, a display unit 1502 includingthe TFT and the organic LED may be arranged on the display substrate1501. Unlike as illustrated in FIG. 14, a first function layer 1504corresponding to encapsulation may be arranged on the display unit 1502.A touch sensor electrode 1503 may be arranged on the first functionlayer 1504. A second function layer 1506, which corresponds to thewindow cover, may be arranged above the touch sensor electrode 1503 witha medium layer 1505 therebetween. A force sensor electrode 1507 may bearranged on one surface of the second function layer 1506. The forcesensor electrode 1507 may be connected to a connector 1509 and maytransfer the force sensor signal to the external device.

The structure described above may sense the force applied in accordancewith the capacitance change between the touch sensor electrode 1503 andthe force sensor electrode 1507.

Referring to FIG. 16, a display device 1600 may be a liquid crystaldisplay device. In detail, a display unit 1602 including a crystaldisplay element may be arranged on the display substrate 1601, and atouch sensor electrode 1603 may be arranged on the display unit 1602. Afunction layer 1604, which corresponds to a color filter substrate, maybe arranged on the touch sensor electrode 1603, and a force sensorelectrode 1605 may be arranged on the function layer 1604. The forcesensor electrode 1605 may be connected to a connector 1606 and maytransfer the force sensor signal to the external device.

The structure described above may sense the applied force via thecapacitance change between the touch sensor electrode 1603 and the forcesensor electrode 1605.

Referring to FIG. 17, a display device 1700 may be a liquid crystaldisplay device. In detail, a display unit 1702 including a crystaldisplay element may be arranged on a display substrate 1701. Unlike asillustrated in FIG. 16, a first function layer 1704, which correspondsto a color filter substrate, may be arranged on the display unit 1702and a touch sensor electrode 1703 may be arranged on the first functionlayer 1704. A second function layer 1708 such as the window cover may bearranged above the touch sensor electrode 1703 with a medium layer 1707therebetween. A force sensor electrode 1705 may be arranged on onesurface of the second function layer 1708. The force sensor electrode1705 may be connected to a connector 1706 and may transfer the forcesensor signal to the external device.

The structure described above may sense the applied force via thecapacitance change between the touch sensor electrode 1703 and the forcesensor electrode 1705.

Referring to FIG. 18, a display device 1800 may include a displaysubstrate 1801. A display unit 1802 may be arranged on the displaysubstrate 1801. The display unit 1802 may include a micro-LED. A touchsensor electrode 1803 may be arranged on the display unit 1802. Inanother exemplary embodiment, the display unit 1802 may include a LCDelement, or an organic LED. In another exemplary embodiment, a functionlayer such as a color filter substrate or an encapsulation layer may bearranged on the display 1802.

A function layer 1809, which corresponds to the window cover, may bearranged above the touch sensor electrode 1803 with a medium layer 1810therebetween. A force sensor electrode 1805 may be arranged on afunction layer 1809 facing the touch sensor electrode 1803.

According to an exemplary embodiment, the medium layer 1810 may includean air layer. A refractive index matching layer (“RIML”) 1806 may bearranged on at least one surface of the force sensor electrode 1805 toimprove reflective index affected by the air layer. The RIML 1806 mayinclude a first RIML 1807 arranged on one surface of the force sensorelectrode 1805 facing the touch sensor electrode 1803 and a second RIML1808 arranged on the other surface of the force sensor electrode 1805facing the function layer 1809.

In an exemplary embodiment, the RIML 1806 may include silicon oxide(SiO₂) or silicon nitride (SiNx), for example. The refractive index ofthe first RIML 1807 and that of the second RIML 1808 may be less thanthat of the force sensor electrode 1805. The RIML 1806 with a lowrefractive index and the force sensor electrode 1805 with a highrefractive index are alternately arranged on the medium layer 1810.Thus, the refractive index of the display device 1800 may be improvedand poor show-through of the touch sensor electrode 1803 may beimproved.

FIG. 19 is a cross-sectional view of a single sub-pixel according toanother exemplary embodiment.

Referring to FIG. 19, the display device 1900 may include the pluralityof sub-pixel areas 301. The sub-pixel area 301 may include the firstarea 302 in which the LED 325 is placed and the second area 303 in whichthe touch sensor electrode 1926 is placed. The touch sensor electrode1926 may extend to an adjacent sub-pixel area 301.

According to an exemplary embodiment, the touch sensor electrode 1926may include a first touch electrode 1927 and a second touch electrode1928. The first touch electrode 1927 and the first electrode 333 may bearranged on the same layer. In another exemplary embodiment, the firsttouch electrode 1927 and at least one of the gate electrode 318, thesource electrode 320, and the drain electrode 321, which are arranged onthe TFT, may be arranged on the same layer.

A first bank 1903 may be arranged on the circumference of the sub-pixelarea 301. The LED 325 and the first touch electrode 1927 may be arrangedin the opening 324 with a portion of the first bank 1903 removedtherefrom.

A second bank 1904 may be further arranged on the first bank 1903. Thesecond bank 1904 may embed the LED 325 and the first touch electrode1927. The second bank 1904 may planarize the top surface of the LED 325.

The second electrode 334 may be electrically connected to the LED 325 onthe second bank 1904. The second touch electrode 1928 and the secondelectrode 333 may be arranged on the same layer. The touch sensorelectrode 1926 may correspond to an electrode which senses thecapacitance change between the first touch electrode 1927 and the secondtouch electrode 1928.

A color filter 1901 may be arranged over the LED 325. The color filter1901 may transform light emitted from the LED 325 or increase colorpurity.

A black matrix 1902 may be arranged on the circumference of the colorfilter 1901. The black matrix 1902 may surround the circumference of theLED 325. In another exemplary embodiment, the black matrix 1902 may bearranged between adjacent sub-pixel areas 301. Since the color filter1901 and the black matrix 1902 are arranged, a polarization plate is notneeded and reflection of external light may be improved.

An encapsulation layer 1905 may be arranged on the outermostcircumference of the display substrate 311 to protect each elementarranged on the display substrate 311. The encapsulation layer 1905 mayinclude a lamination of at least one of inorganic materials and at leastone of organic materials. In another exemplary embodiment, theencapsulation layer 1905 may include an inorganic material.

FIG. 20 is a cross-sectional view of a single sub-pixel according toanother exemplary embodiment.

Referring to FIG. 20, the display device 2000 may include the pluralityof sub-pixel areas 301. The sub-pixel area 301 may include the firstarea 302 in which the LED 325 is placed and the second area 303 in whicha touch sensor electrode 2026 is placed. The touch sensor electrode 2026may extend to an adjacent sub-pixel area 301. According to an exemplaryembodiment, the touch sensor electrode 2026 may include a first touchelectrode 2027 and a second touch electrode 2028. The first touchelectrode 2027 and the first electrode 333 may be arranged on the samelayer. In another exemplary embodiment, the first touch electrode 2027and at least one of the gate electrode 318, the source electrode 320,and the drain electrode 321, which are provided in the TFT, may bearranged on the same layer.

A first bank 2003 may be arranged on the circumference of the sub-pixelarea 301. The first bank 2003 may extend to an adjacent sub-pixel area301. The LED 325 and the first touch electrode 2027 may be arranged inthe opening 324 which is provided by removing the portion of the firstbank 2003.

A second bank 2004 may be further arranged on the first bank 2003. Thesecond bank 2004 may embed the LED 325 and the first touch electrode2027. The second bank 2004 may be independently arranged on respectivesub-pixel areas 301 such that the LEDs 325 are embedded.

According to an exemplary embodiment, the second bank 2004 may extendfrom the first area 302 in which the LED 325 is placed to the secondarea 302 in which the touch sensor electrode 2026 is placed. In anotherexemplary embodiment, the second bank 2004 may be arranged on only thefirst area 302 including the LED 325.

According to an exemplary embodiment, the second bank 2004 may include ascattering material or a color conversion material.

The second electrode 334 may be electrically connected to the LED 325 onthe second bank 2004. A second touch electrode 2028 and the secondelectrode 334 may be arranged on the same layer. The second touchelectrode 2028 may correspond to an electrode which senses thecapacitance change between the first touch electrode 2027 and the secondtouch electrode 2028.

A color filter 2001 may be arranged above the LED 325. The color filter2001 may transform light emitted from the LED 325 or increase colorpurity.

A black matrix 2002 may be arranged on the circumference of the colorfilter 2001. According to an exemplary embodiment, the black matrix 2002may surround the circumference of the LED 325. In another exemplaryembodiment, the black matrix 2002 may be arranged between adjacentsub-pixel areas 301.

An encapsulation layer 2005 may be arranged on the outermostcircumference of the display substrate 311 to protect each elementarranged on the display substrate 311. The encapsulation layer 2005 mayinclude a lamination of at least one of inorganic materials and at leastone of organic materials.

It should be understood that the exemplary embodiments described hereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or exemplary embodiments withineach exemplary embodiment should typically be considered as availablefor other similar features or exemplary embodiments in other exemplaryembodiments.

While one or more exemplary embodiments have been described withreference to the figures, it will be understood by those of ordinaryskill in the art that various changes in form and details may be madetherein without departing from the spirit and scope as defined by thefollowing claims.

What is claimed is:
 1. A display device comprising: a display substratein which a plurality of sub-pixel areas is defined; a light-emittingdiode above the display substrate; a touch sensor electrode above thedisplay substrate and including at least one touch electrode; touchsensor wirings which are respectively and electrically connected to thetouch sensor electrode and reciprocally exchange electrical signals ofthe touch sensor electrode with an external device; and a bankseparating the plurality of the sub-pixel areas, wherein each of theplurality of sub-pixel areas comprises a first area in which thelight-emitting diode is disposed and a second area in which the touchsensor electrode is disposed, wherein each of the plurality of sub-pixelareas is positioned in an opening surrounded by the bank, and wherein afilling layer is arranged in the opening, the light-emitting diode andthe touch sensor electrode are embedded in the filling layer, and thetouch sensor wirings are electrically connected to the touch sensorelectrode via a contact hole and are arranged on the filling layer.